Redesign the copresence audio handlers.

chrome/browser/resources/whispernet_proxy/js/wrapper.js

Index: chrome/browser/resources/whispernet_proxy/js/wrapper.js
diff --git a/chrome/browser/resources/whispernet_proxy/js/wrapper.js b/chrome/browser/resources/whispernet_proxy/js/wrapper.js
index 7c3262b1c5823fdcc6e280e47794b8337dfa2e28..064088d5139097fdeaaa0f3ace1a06f10a54b753 100644
--- a/chrome/browser/resources/whispernet_proxy/js/wrapper.js
+++ b/chrome/browser/resources/whispernet_proxy/js/wrapper.js
@@ -49,7 +49,7 @@ function WhisperEncoder(params, whisperNacl) {
     sample_rate: params.sampleRate || 48000.0,
     upsampling_factor: params.bitsPerSample || 16,
   };
-  this.whisperNacl_.send(JSON.stringify(msg));
+  this.whisperNacl_.send(msg);
 }
 
 /**
@@ -71,7 +71,7 @@ WhisperEncoder.prototype.encode = function(token, audible, raw) {
     use_dtmf: audible,
     return_raw_samples: raw
   };
-  this.whisperNacl_.send(JSON.stringify(msg));
+  this.whisperNacl_.send(msg);
 };
 
 /**
@@ -119,7 +119,7 @@ function WhisperDecoder(params, whisperNacl) {
     max_candidates: 1,
     max_buffer_duration_in_seconds: 3
   };
-  this.whisperNacl_.send(JSON.stringify(msg));
+  this.whisperNacl_.send(msg);
 }
 
 /**
@@ -129,7 +129,7 @@ WhisperDecoder.prototype.wipeDecoder = function() {
   var msg = {
     type: 'wipe_decode_buffer'
   };
-  this.whisperNacl_.send(JSON.stringify(msg));
+  this.whisperNacl_.send(msg);
 };
 
 /**
@@ -139,17 +139,34 @@ WhisperDecoder.prototype.detectBroadcast = function() {
   var msg = {
     type: 'detect_broadcast'
   };
-  this.whisperNacl_.send(JSON.stringify(msg));
+  this.whisperNacl_.send(msg);
 };
 
 /**
  * Method to request the decoder to process samples.
+ * @param {string} type Type of decoding to perform.
  * @param {ArrayBuffer} samples Array of samples to process.
  */
-WhisperDecoder.prototype.processSamples = function(samples) {
-  // For sample processing, the Nacl module doesn't expect any frills in the
-  // message, just send the samples directly.
-  this.whisperNacl_.send(samples);
+WhisperDecoder.prototype.processSamples = function(type, samples) {
+  // We set the type value to 01b for audible, 10b for inaudible and 11b for
+  // both. This is due to not having any other way of actually sharing enum
+  // values across JS/Nacl boundaries - hence, viva la 1980's coding vida!
+  var typeVal = 0;
+  if (type == 'audible') {
+    typeVal = 1;
+  } else if (type == 'inaudible') {
+    typeVal = 2;
+  } else if (type == 'both') {
+    typeVal = 3;
+  }
+
+  var msg = {
+    type: 'decode_tokens',
+    request_type: typeVal,
+    data: samples,
+  };
+
+  this.whisperNacl_.send(msg);
 };
 
 /**
@@ -179,7 +196,7 @@ WhisperDecoder.prototype.onDetectBroadcast = function(callback) {
 WhisperDecoder.prototype.onNaclMessage_ = function(e) {
   var msg = e.data;
   if (msg.type == 'decode_tokens_response') {
-    this.handleCandidates_(JSON.parse(msg.tokens), msg.audible);
+    this.handleCandidates_(msg.tokens, msg.audible);
   } else if (msg.type == 'detect_broadcast_response') {
     this.detectBroadcastCallback_(msg.detected);
   }